Directed Energy Weapons

In The Kill Chain, directed energy weapons — “lasers and high-powered microwaves” — appear as one of the future surface areas reshaping the offense-defense balance of warfare. Christian Brose flags them alongside hypersonics, electromagnetic railguns, and hypervelocity projectiles in a related arms race: as new high-speed weapons proliferate, much of the focus shifts to directed energy as the counter. The book notes the US government “has spent billions of dollars over several decades trying to develop it,” and that for the first time these weapons are “actually operationally viable.”

The economic argument is the heart of why Brose cares about them. Their advantage is the ability “to shoot more often, much faster, at lower cost, and without the burden of resupplying ammunition.” Where a traditional missile can cost upward of $1 million per shot — and the platform carrying it eventually runs out of weapons — a directed energy shot could cost “as little as a few” dollars. That cost-per-shot inversion is precisely the kind of paradigm disruption the book argues the US defense establishment is too slow to capitalize on, with many of the most consequential technologies being developed by commercial firms uninterested in selling to the military. Brose also notes the symmetry: adversaries already field lasers “to blind satellites,” and the race to build counters — “mirrors and heat shields” — has already begun. At present, he writes, these systems are “like early firearms, somewhat clumsy and of limited use now.”

Context: Directed energy weapons use concentrated electromagnetic energy — high-energy lasers, high-powered microwaves, particle beams — rather than kinetic projectiles to disable or destroy targets. Their appeal for missile and drone defense is a near-instantaneous, low-cost-per-shot engagement limited mainly by available electrical power.

Where this appears

• The Kill Chain — listed among future defense surface areas; Brose uses the radically low cost-per-shot to illustrate the kind of weapons paradigm shift the US military is structurally too slow to adopt